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Morphing wing flaps for large civil aircraft:Evolution of a smart technology across the Clean Sky program

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Chinese Journal of Aeronautics 2021年第7期34卷 13-28页

作者： Rosario Pecora Department of Industrial Engineering Aerospace DivisionUniversity of Naples“Federico II”80125 NapoliItaly

Abstract Morphing wing structures are widely considered among the most promising technologies for the improvement of aerodynamic performances in large civil *** controlled adaptation of the wing shape to external operative conditions naturally enables the maximization of aircraft aerodynamic efficiency,with positive fallouts on the amount of fuel burned and pollutant *** benefits brought by morphing wings at aircraft level are accompanied by the criticalities of the enabling technologies,mainly involving weight penalties,overconsumption of electrical power,and safety *** attempt to solve such criticalities passes through the development of novel design approaches,ensuring the consolidation of reliable structural solutions that are adequately mature for certification and in-flight *** this work,the development phases of a multimodal camber morphing wing flap,tailored for large civil aircraft applications,are outlined with specific reference to the activities addressed by the author in the framework of the Clean Sky *** flap is morphed according to target shapes depending on aircraft flight conditions and defined to enhance high-lift performances during takeoff and landing,as well as wing aerodynamic efficiency during *** innovative system based on finger-like robotic ribs driven by electromechanical actuators is proposed as morphing-enabling technology;the maturation process of the device is then traced from the proof of concept to the consolidation of a true-scale demonstrator for pre-flight ground validation tests.A step-by-step approach involving the design and testing of intermediate demonstrators is then carried out to show the compliance of the adaptive system with industrial standards and safety *** technical issues encountered during the development of each intermediate demonstrator are critically analyzed,and justifications are provided for all the adopted engineering ***,the layout

关键词： Electro-mechanical actuators(EMA) Green regional aircraft Mechanical systems Morphing flap Morphing wing Smart aircraft Smart structures Variable camber airfoil

A novel coordinated control for NZEB clusters to minimize their connected grid overvoltage risks

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Building Simulation 2022年第10期15卷 1831-1848页

作者： Yelin Zhang Norman Chung Fai Tse Haoshan Ren Yongjun Sun division of Building Science and Technology City University of Hong KongKowloonHong KongChina

The increasing applications of net-zero energy buildings (NZEBs) will lead to more frequent and larger energy interactions with the connected power grid, thereby being able to result in severe grid overvoltage risks. Control optimization has been proven effective to reduce such risks. Existing controls have oversimplified the overvoltage quantification by simply using the aggregated power exchanges to represent the connected grid overvoltages. Ignoring the complex voltage influences among the grid nodes, such oversimplification can easily result in low-accuracy impact evaluations of the NZEB-grid energy interactions, thereby causing non-optimal/unsatisfying overvoltage mitigations. Therefore, this study proposes a novel coordinated control method in which a power-distribution-network model has been adopted for more accurate overvoltage quantification. Meanwhile, the battery operations of individual NZEBs are iteratively coordinated using a sequential optimization approach for achieving the global optimum with substantially reduced computation complexity. For verifications, the proposed coordinated control has been systematically compared with an uncoordinated control and a conventional coordinated control in grid overvoltage minimization. The study results show that the overvoltage improvements can reach 23.5% and 12.3% compared with the uncoordinated control and the conventional coordinated control, respectively. The reasons behind the improvements have also been analyzed in detail. The proposed coordinated control can be used in practice to improve NZEB-clusters’ grid friendliness.

关键词： net-zero energy building coordinated control optimization,genetic algorithm overvoltage quantification grid friendliness

Possible Impacts of Climate Change on Daily Streamflow and Extremes at Local Scale in Ontario, Canada. Part I: Historical Simulation

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Atmospheric and Climate Sciences 2012年第4期2卷 416-426页

作者： Chad Shouquan Cheng Qian Li Guilong Li Heather Auld Adaptation and Impacts Research division Science and Technology Branch Environment Canada Toronto Canada Science Section Operations—Ontario Meteorological Service of Canada Environment Canada Toronto Canada

The paper forms the first part of an introduction to possible impacts of climate change on daily streamflow and extremes in the Province of Ontario, Canada. In this study, both conceptual and statistical streamflow simulation modeling theories were collectively applied to simulate daily streamflow volumes. Based on conceptual rainfall-runoff modeling principle, the predictors were selected to take into account several physical factors that affect streamflow, such as (1) current and previous quantities of rainfall over the watershed, (2) an index of pre-storm moisture conditions, (3) an index of pre-storm evapotranspiration capacities, and (4) a seasonal factor representing seasonal variation of streamflow volume. These rainfall-runoff conceptual factors were applied to an autocorrelation correction regression procedure to develop a daily streamflow simulation model for each of the four selected river basins. The streamflow simulation models were validated using a leave-one-year-out cross-validation scheme. The simulation models identified that the explanatory predictors are consistent with the physical processes typically associated with high-streamflow events. Daily streamflow simulation models show that there are significant correlations between daily streamflow observations and model validations, with model R2s of 0.68-0.71, 0.61-0.62, 0.71-0.74, and 0.95 for Grand, Humber, Upper Thames, and Rideau River Basins, respectively. The major reason for the model performance varying across the basins might be that rainfall-runoff response time and physical characteristics differ significantly among the selected river basins. The results suggest that streamflow simulation models can be used to assess possible impacts of climate change on daily streamflow and extremes at a local scale, which is major objective of a companion paper (Part II).

关键词： Rainfall-Related Streamflow Simualtion Statistic Methods Ontario Canada

Guest editorial-special issue on ground control in mining in 2018

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International Journal of Mining Science and Technology 2019年第1期29卷 1-2页

作者： Michael M.Murphy Ted Klemetti Heather Lawson Brijes Mishra Kyle Perry Pittsburgh Mining Research division NIOSH Spokane Mining Research division NIOSH Mining Engineering West Virginia University Mining&Nuclear Engineering Missouri S&T

Ground control is the science of studying and controlling the behavior of rock strata in response to mining operations. Ground control-related research has seen significant advancements over the last 37 years, and these accomplishments are well documented in the proceedings of the annual International Conference on Ground Control in Mining (ICGCM)(1)The ICGCM is a forum to promote closer communication among researchers, consultants。

关键词： NIOSH Guest editorial-special issue on ground control in mining in 2018

Minimally invasive surgical approach to pancreatic malignancies

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World Journal of Gastrointestinal Oncology 2015年第12期7卷 411-421页

作者： Lapo Bencini Mario Annecchiarico Marco Farsi Ilenia Bartolini Vita Mirasolo Francesco Guerra Andrea Coratti Department of Oncology Division of Surgical Oncology and Robotics Careggi University Hospital

Pancreatic surgery for malignancy is recognized as challenging for the surgeons and risky for the patientsdue to consistent perioperative morbidity and mortality. Furthermore, the oncological long-term results are largely disappointing, even for those patients who experience an uneventfully hospital stay. Nevertheless, surgery still remains the cornerstone of a multidisciplinary treatment for pancreatic cancer. In order to maximize the benefits of surgery, the advent of both laparoscopy and robotics has led many surgeons to treat pancreatic cancers with these new methodologies. The reduction of postoperative complications, length of hospital stay and pain, together with a shorter interval between surgery and the beginning of adjuvant chemotherapy, represent the potential advantages over conventional surgery. Lastly, a better cosmetic result, although not crucial in any cancerous patient, could also play a role by improving overall well-being and patient self-perception. The laparoscopic approach to pancreatic surgery is, however, difficult in inexperienced hands and requires a dedicated training in both advanced laparoscopy and pancreatic surgery. The recent large diffusion of the da Vinci® robotic platform seems to facilitate many of the technical maneuvers, such as anastomotic biliary and pancreatic reconstructions, accurate lymphadenectomy, and vascular sutures. The two main pancreatic operations, distal pancreatectomy and pancreaticoduodenectomy, are approachable by a minimally invasive path, but more limited interventions such as enucleation are also feasible. Nevertheless, a word of caution should be taken into account when considering the increasing costs of these newest technologies because the main concerns regarding these are the maintenance of all oncological standards and the lack of long-term follow-up. The purpose of this review is to examine the evidence for the use of minimally invasive surgery in pancreatic cancer(and less aggressive tumors), w

关键词： Pancreatic cancer Pancreatic adenocarcinoma Neuroe

Influence of hysteretic stress path behavior on seal integrity during gas storage operation in a depleted reservoir

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第4期12卷 886-899页

作者： Pierre Jeanne Yingqi Zhang Jonny Rutqvist Lawrence Berkeley National Laboratory Energy Geosciences DivisionBerkeleyCA94720USA

In this study,we numerically investigate the influence of hysteretic stress path behavior on the seal integrity during underground gas storage operations in a depleted *** study area is the Honor Rancho Underground Storage Facility in Los Angeles County(California,USA),which was converted into an underground gas storage facility in 1975 after 20 years of oil and gas *** our simulations,the geomechanical behavior of the sand reservoir is modeled using two models:(1)a linear elastic model(non-hysteretic stress path)that does not take into consideration irreversible deformation,and(2)a plastic cap mechanical model which considers changes in rock elastic properties due to irreversible deformations caused by plastic reservoir compaction(hysteretic stress path).It shows that the irreversible compaction of the geological layer over geologic time and during the reservoir depletion can have important consequences on stress tensor orientation and *** depletion-induced irreversible compaction can lead to an over-estimation of the calculation of the maximum working reservoir ***,this irreversible compaction may bring the nearby faults closer to ***,regardless of the two models applied,the geomechanical analysis shows that for the estimated stress conditions applied in this study,the Honor Rancho Underground Storage Facility is being safely operated at pressures much below what would be required to compromise the seal integrity.

关键词： Gas storage Stress path Geomechanical simulation Caprock integrity Fault stability Modified cam-clay model Honor rancho underground storage facility

A data directory to facilitate investigations on worldwide wildlife trafficking

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Big Earth Data 2023年第2期7卷 338-348页

作者： Meredith L.Gore Rowan Hilend Jonathan OPrell Emily Griffin John R.Macdonald Burcu B.Keskin Aaron Ferber Bistra Dilkina Department of Geographical Sciences University of MarylandCollege ParkUSA Department of Supply Chain Management Michigan State UniversityEast LansingUSA Department of Information Sciences Statisticsand Management ScienceUniversity of AlabamaTuscaloosaUSA operations and Information Management division Babson CollegeWellesleyUSA Supply Chain Management Department of ManagementColorado State UniversityFort CollinsUSA Verterbi School of Engineering University of Southern CaliforniaLos AngelesUSA

Wildlife trafficking is a global phenomenon posing many negative impacts on socio-environmental *** exploration of wildlife trafficking trends and the impact of interventions is significantly encumbered by a suite of data reuse *** describe a novel,open-access data directory on wildlife trafficking and a corresponding visualization tool that can be used to identify data for multiple purposes,such as exploring wildlife trafficking hotspots and convergence points with other crime,discovering key drivers or deterrents of wildlife trafficking,and uncovering structural *** searches,expert elicitation,and peer-reviewed publications were used to search for extant sources used by industry and non-profit organizations,as well as those leveraged to publish academic research *** open-access data directory is designed to be a living document and searchable according to multiple *** directory can be instrumental in the data-driven analysis of unsustainable illegal wildlife trade,supply chain structure via link prediction models,the value of demand and supply reduction initiatives via multi-item knapsack problems,or trafficking behavior and transportation choices via network interdiction problems.

关键词： Illegal wildlife trade supply chain operations management interdiction conservation

Experimental Investigation and Numerical Analysis to Develop Low-Energy Large-Midwater Trawls

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China Ocean Engineering 2017年第6期31卷 700-708页

作者： Jihoon LEE Taeho KIM Chun-Woo LEE Subong PARK division of Marine Technology Chonnam National University Yeosu 550-749 Korea division of Marine Production System Management Pukyong National University Busan 608-737 Korea Department of Fisheries Physics Pukyong National University Busan 608-737 Korea

Fuel consumption in fisheries is a primary concern because of its effects on the environment and the costs incurred by fishermen. Many studies have been conducted to reduce the fuel consumption in fishing operations. Fuel consumption due to fishing gear during a fishing operation is generally related to the hydrodynamic resistance on the gear. This means that fuel consumption is proportional to the drag created by the towing speed. Based on numerical methods, this study suggests a new approach to reduce fuel consumption in fisheries. The results of the simulation are in good agreement with those of model experiments. The total as well as partial resistance forces on the gear are calculated by simulation. The simulation results suggest improved materials and gear structure for reducing the hydrodynamic forces on the gear while maintaining gear performance. The method for assessing the gear performance involves measuring the height and width of the net mouth. Furthermore, this study investigates the efficiency of a low-energy trawl from an economic point of view. The findings of this study will be useful in reducing greenhouse gas （GHG） emissions in fishing operations, and thereby contribute toward lowering fishing costs by saving fuel.

关键词： low-energy fishing gear numerical methods greenhouse gasesemission hydrodynamic resistance fuelconsumption

Managing Dynamics in Corporate Networks

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World Journal of Engineering and Technology 2014年第1期2卷 32-40页

作者： Mike Danilovic Mats Winroth Centre of Innovation Entrepreneurship and Learning Research School of Business and Engineering Halmstad University Halmstad Sweden division of operations Management Department of Technology Management and Economics Chalmers University of Technology Gothenburg Sweden

A crucial issue in collaborating in manufacturing corporate networks between different companies is to identify to what extent different strategic and operational decisions need to be coordinated between the involved companies. In this paper, we elaborate on the issue of synchronization and coordination of information flow based on interconnectivities between companies in order to coordinate a corporate network by the means of DSM, Dependence Structure Matrix. The results show that DSM can be used to identify interconnectivities, dependencies on information flow among actors in a network and to identify which information needs to be shared between companies in the network.

关键词： Corporate Network Supplier Collaboration Design Structure Matrix